The present invention relates to an arrangement for interlocking a two or more overlapped paperboard panels, such as is done in connection with paperboard cartons for packaging. More particularly, the invention relates to such an arrangement which includes means for releasing the locking arrangement when it is desired to remove the packaged product or products from the carton.
Locking arrangements for use in connection with paperboard cartons are well known. A simple punch-type lock can be seen by reference to U.S. Pat. No. 3,128,010. A locking tab is foldably connected to a first panel, while a second, underlying panel includes an aperture covered by a retention tab which is aligned with the tab. The tab is driven through the aperture to secure the panels together. An important consideration for locking devices of this type is retention of the locking tab in position. As can be readily recognized, it is important that the locking tab not be released when the carton is in use for carrying product. Many arrangements for securing the locking tab into its locked position are well known in the art.
A further example of a retention tab may be seen by reference to U.S. patent application Ser. No. 08/060,866. There, a top-gripping carrier for bottles is shown on which the bottles are secured by positioning of the bottle necks in apertures formed in upper and lower panels of the carrier. The bottle-receiving apertures are formed of a generally keyhole shape so that sliding movement of the upper and lower panels with respect to each other secures the bottles. The panels are in turn fixed into their relative positions by a punch-lock arrangement wherein a locking tab is driven into a receiving aperture.
It may be difficult or awkward for the purchaser of such a package to remove the bottles from the carrier for use. One possibility is to release the locking tabs and move the panels with respect to each other in a reverse operation of the packaging of the product. However, the locking tabs are designed not to be easily released to avoid unwanted opening of the package. The tabs are located in a relatively crowded portion of the package, being positioned near the bottle necks and several overlapped paperboard panels, making manipulation of the tabs difficult. Further, it is not immediately obvious to the user how the operation may be performed. A second alternative is to simply tear the carton, although the several layers of paperboard in close proximity to each other make even this approach difficult.
It is known to provide perforated tear strips in the walls of a paperboard carton to simplify release of the packaged product. However, this may reduce the strength of the carrier and assures that the carrier cannot be reused, for example, to carry empty bottles back to the point of purchase for recycling and/or refund.
What is needed, therefore, is an improved release means for use with locking arrangements for paperboard cartons. Such a means should be relatively easy to use and understand, but should not detract from the performance or appearance of the carton.